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Bu çalışmada, Bursa’da 2008 ile 2016 yılları arasında kullanılan kimyasal gübre türleri yapılarına göre sınıflandırılarak yıllık miktarları ve ilçelere göre kullanım miktarları hesaplanmıştır. İlçelerde kullanılan gübre türleri Coğrafi Bilgi Sistemi ile haritalandırılarak tarımsal ürün çeşitleri ile gübre türleri arasındaki istatistiksel ilişkiler korelasyon ve regresyon analizi ile değerlendirilmiştir. Bursa’da nüfus ve ihracatın artması nedeniyle tarımsal üretim ile birlikte gübre kullanımı artmıştır. Azot içeren gübrelerin diğer gübre grupları arasında en yüksek kullanıma sahip olduğu belirlenmiştir. Azotlu (maksimum 82,47 kg/ha- Karacabey), azot, fosfor ve potasyumlu (maksimum 31,59 kg/ha-Karacabey), kalsiyum nitratlı (maksimum 8,1 kg/ha-Yenişehir) ve azot ve fosforlu (maksimum 58,45 kg/ha-Yenişehir) gübrelerin kullanımı en çok Karacabey, Yenişehir, Mustafakemalpaşa ve İnegöl’de bulunmuştur. Triple Süper Fosfat (TSP) (maksimum 12,5 kg/ha-Gürsu) ve Zn’li (maksimum 26,84 kg/ha-Gemlik) gübreler Gürsu, Orhangazi, Mudanya, Gemlik ve İznik’te daha fazla kullanılmıştır. En yüksek korelasyon (r2) değerleri azot, fosfor ve potasyumlu gübreler ile tarla bitkileri ve sebze üretimi arasında (0,423-0,788) bulunmuştur. Ayrıca, azotlu, azotlu ve fosforlu ve azot, fosfor ve potasyumlu gübrelerin bitkisel üretim ile pozitif ilişkili ve üretimde etkili olduğu belirlenmiştir. Bu çalışma yayılı kirlilik kaynağı olan tarımsal gübre kullanımının il bazındaki dağılımının belirlenebilmesi ve kirliliğin azaltılması için yapılabilecek gübre yönetimi çalışmalarına bilgi sağlaması açısından önemlidir., In this study, fertilizer types used in Bursa province between 2008 and 2016 were classified according to their chemical structure and their annual usage according to districts were calculated per unit of land. Amount of the fertilizer types used in districts were mapped with Geographical Information System and the statistical relationships between the types of agricultural product and fertilizer were calculated by correlation and regression analysis. Due to the increase in population and exports of Bursa, the fertilizer usage with agricultural production increased. Nitrogen fertilizers were determined to have the highest usage among other fertilizer groups. The usages of fertilizers of nitrogen (maximum 82.47 kg/ha-Karacabey), nitrogen phosphorus potassium (maximum 31.59 - kg/ha-Karacabey), and calcium nitrate (maximum 8.1 kg / ha-Yenişehir), nitrogen and phosphorus (maximum 58.45 kg/ha-Yenişehir) were more found in Karacabey, Yenişehir, Mustafakemalpaşa ve İnegöl. TSP (maximum 12.5 kg / ha-Gürsu) and zinc (maximum 26.84 kg / ha-Gemlik) fertilizers were used more in Gürsu, Orhangazi, Mudanya, Gemlik and İznik than the other districts. The higher correlation (r2) values than the others were found between nitrogen, phosphorus and potassium fertilizers and field crops and vegetable production (0.423-0.788). Nitrogenous, nitrogenous and phosphorous and nitrogen, phosphorus and potassium fertilizers were found to be positively related to crop production and effective in production. This study is important in order to determine the distribution of agricultural fertilizer usage, which is the diffuse pollution source, by districts and to provide information to fertilizer management studies that could be done to reduce pollution.

In this study, fully recyclable and elastic–plastic deformable sandwich panels were developed by considering the mass production requirements, as well as the lightweighting needs of the automotive industry. Expanded polypropylene (EPP) foam core and self-reinforced polypropylene (PP) thermoplastic composite face sheets were selected to produce sandwich panels. Three-point bending experiments were performed to obtain the flexural behavior of the sandwich panels. Finite-element analysis (FEA) of the sandwich beams was carried out and confirmed by experimental results. Three different EPP foam cores with densities of 65.7, 36.5 and 27.0 kg/m3 were used. The FEA models were built in the Abaqus commercial software in three-dimensional (3D) space, and analyses were performed using 3D elements. The crushable foam material model was selected for FEA from the Abaqus material model database to obtain the best correlation with the foam compression test results. The force–displacement results of the three-point bending FEA results excellently correlated with the experiments. In three-point bending experiments of the sandwich panels, elastic–plastic deformation of the core with indentation failure was observed. The lowest-density foam core sandwich beam showed the highest deformation and energy absorption performance. Also, deflection recovery was observed after load removal for all sandwiches.

Utilizing electricity from renewable resources is very attractive to decrease the dependence on fossil fuels. As a result, hybrid power systems are gaining more attention. This paper focuses on the optimal design and dynamic simulation of renewable-based, hybrid standalone power systems. The designed system is able to meet the energy need of a building with 5 kW peak electricity demand. Both the technical and economic feasibility of the system was investigated under various climatic conditions of Turkey. Diesel fuel consumption, energy cost and annual CO2 emissions were estimated and compared with the diesel generator-only system. A parametric analysis was also conducted to understand the impact of the capacity of the PV array, wind turbine and the battery on the CO2 emissions and the levelized cost of energy. The system in each location was optimized based on the minimum energy cost and CO2 emissions. (C) 2020 Elsevier Ltd. All rights reserved.

In this paper, the effect of degumming processes on the physical performance, surface properties and colour coordinates of silk fabrics at high temperature and enzymatically, which was developed as an alternative to conventional method, has been investigated. Degummed silk fabrics were compared in terms of weight loss, bending length, tear and breaking strength, surface roughness and friction coefficient. After these tests, acid dyeing was performed to observe different degumming methods effect on dyeing behaviour of degummed silk fabric. The colour coordinates were evaluated by L*, a*, b*, C*, h0, K/S, and ∆E* values. The results revealed that despite insignificant differences between conventional and alternative methods in terms of physical performance and surface properties, the conventional method gave slightly better results than the others. There were no significant differences in colour depth between the two processes. These reasons showed that the alternative method could be used instead of the traditional method and a more sustainable process has been designed

In today’s world, reducing fuel consumption is one of the most important goals for the automotive industry. For this reason, weight reduction is one of the main topics in this research and for various companies. In this research, topology optimization was conducted on a suspension arm as a means of ensuring balance in automobiles. Subsequently, the model, formed by topology optimization was filled with a lattice structure and re-optimized by size optimization to obtain optimum dimensions for the model. These operations are described as lattice structure optimization. Additive manufacturing (3D printer) is necessary to produce complex models (after topology and lattice structure optimization). A static analysis of the new models was conducted by using the finite element method, and the results were compared with those of the initial design of the model. As a result of the comparison, positive results were obtained, and it was shown that topology optimization and lattice structural optimization could be used in the design of vehicle elements. According to the results obtained from lattice structure optimization, design structure can be formed more reliably than via topology optimization. In addition, both configurations and layouts of the cellular structures have a special effect on the overall performance of the lattice structure.

The shape optimization of mechanical and automotive component plays a crucial role in the development of automotive technology. Presently, the use of derivative-free metaheuristics in combination with finite element analysis for mechanical component design is one of the most focused on topics due to its simplicity and effectiveness. In this research paper, the mine blast algorithm (MBA) is used to solve the problem of shape optimization for a vehicle door hinge to prove how the MBA can be used for solving shape optimization problems in designing electrical vehicles. The results show the advantage of the MBA for designing optimal components in the automotive industry.

This work presents a thermodynamic evaluation of an operating geothermal ORC power plant. The model is realized by using measured data of AFJET geothermal power plant which has 3MWe net power output capacity. Thermodynamic assessment of the system is conducted to see the energy and exergy efficiencies of each component, and the whole plant. Additionally, a parametric study is conducted to understand the effects of various operating conditions on the system performance. Different from previous studies, daily and annual net power output profile of the plant was investigated with considering ambient temperature fluctuations. Results revealed that net power output can drop as significant as 36% from winter to summer months. Also, between nighttime to daytime, the net power expectation may decrease by 5%. The exergy destruction rate of re-injection process constitutes the most significant part (38.1%) of the total exergy destruction of the plant. The conversion and exergy efficiencies of the system are calculated as 11.24% and 39.03%, respectively. Also, to enhance the performance of the plant, an internal heat recovery system is recommended. The analyses show that the implementation of an internal heat recovery system improves the energy and exergy efficiencies of the plant by 15%.

In the presented study, the performance improvement of Au/PTCDA/n-Si diodes was demonstrated with the help of pre-irradiation of PTCDA powders. The crystallographic analysis was carried out by X-ray diffraction method after the pre-irradiation of PTCDA powders. After the vacuum deposition of pre-irradiated (PI) and unirradiated (UI) PTCDA thin films, the Au/PTCDA/n-Si diodes were fabricated. The I-V, C-V, and G/omega-V characteristics were analyzed for Au/PTCDA/n-Si diodes with UI PTCDA as an interfacial layer (D1-pristine) and PI PTCDA with 30 kGy as an interfacial layer (D2). Radiation-induced effects on the produced diodes were investigated with parameters of the barrier height (phi(Bo)), series resistance (R-s), and the density of interface states (N-SS) and compared to the parameters of the pristine diode. It was observed that the electrical characteristics of Au/PTCDA/n-Si diodes, for D1 and D2, were highly influenced by the irradiation. Thus, the device performance could be improved with the pre-irradiation process. By modifying the HF-LF capacitance method to the UI-PI capacitance method, we successfully calculated the radiation-induced N-SS values without using C-V measurement at two different frequencies.

This paper introduces a new hybrid optimization algorithm (HWOANM) based on the Nelder-Mead local search algorithm (NM) and whale optimization algorithm (WOA). The aim of hybridization is to accelerate global convergence speed of the whale algorithm for solving manufacturing optimization problems. The main objective of our study on hybridization is to accelerate the global convergence rate of the whale algorithm to solve production optimization problems. This paper is the first research study of both the whale algorithm and HWOANM for the optimization of processing parameters in manufacturing processes. The HWOANM is evaluated using the well-known benchmark problems such as cantilever beam problem, welded beam problem, and three-bar truss problem. Finally, a grinding manufacturing optimization problem is solved to investigate the performance of the HWOANM. The results of the HWOANM for both the design and manufacturing problems solved in this paper are compared with other optimization algorithms presented in the literature such as the ant colony algorithm, genetic algorithm, scatter search algorithm, differential evolution algorithm, particle swarm optimization algorithm, simulated annealing algorithm, artificial bee colony algorithm, improved differential evolution algorithm, harmony search algorithm, hybrid particle swarm algorithm, teaching-learning-based optimization algorithm, cuckoo search algorithm, grasshopper optimization algorithm, salp swarm optimization algorithm, mine blast algorithm, gravitational search algorithm, ant lion optimizer, multi-verse optimizer, whale optimization algorithm, and the Harris hawks optimization algorithm. The results show that the HWOANM provides better exploration and exploitation properties, and can be considered as a promising new algorithm for optimizing both design and manufacturing optimization problems.

Smart building equipment and automation systems often become a target of attacks and are used for attacking other targets located out of the Home Area Network. Attacks are often related to changes in traffic volume, disturbed packet flow or excessive energy consumption. Their symptoms can be recognized and interpreted locally, using software agent at Home Gateway. Although anomalies are detected locally at the Home Gateway, they can be exploited globally. Thus, it is significantly important to detect global attack attempts through anomalies correlation. Our proposal in this paper is the involvement of the Network Operator in Home Area Network security. Our paper describes a novel strategy for anomaly detection that consists of shared responsibilities between user and network provider. The proposed two-tier Intrusion Detection System uses a machine learning method for classifying the monitoring records and searching suspicious anomalies across the network at the service provider's data center. Result show that local anomaly detection combined with anomaly correlation at the service providers level can provide reliable information on the most frequent IoT devices misbehavior which may be caused by infection. National Centre for Research and Development (NCBiR) in Poland

Gears are one of the most important power transmission elements in every area of the industry. Because of its importance, the gear design must be carefully performed. Unfortunately, due to the changing of the boundary conditions, gears are exposed to failures such as cracks, pitting, tooth missing etc. during the operation. Thus the gear diagnostic and monitoring become a very critical phenomenon for the gearboxes. A dynamic transmission error (DTE) based numerical fault detection model is proposed. Firstly, numerical finite element model is created to calculate single tooth stiffness with different crack levels. Furthermore, the model is used for the asymmetric gear profile which has a great importance nowadays for different areas. After that, the time-varying mesh stiffness is calculated by using single tooth stiffness with different crack levels for both symmetric and asymmetric types of the gears. To understand the effects of the gear cracks along the tooth thickness on dynamic transmission error of the gear system and to detect the gear crack faults for symmetric and asymmetric gear profiles, a four-degree of freedom dynamic model is created. The results show that with the increment of the crack level, the mesh stiffness of the gears is decreased.

Gear dynamics is one of the most critical subjects in gear design because of its remarkable effect on vibration levels, load-carrying capacity, and noise. The tip relief modification is known as a simple method to decrease dynamic loads in the industry. The primary goal of this study is to understand the influence of tip relief modification on the dynamic performance of the spurs gears. In this paper, the meshing process and gear mesh stiffness calculation method are defined. A dynamic model with two- degree-of-freedom is created to find the dynamic response of the spur gear pair. The simulations are carried out with standard and different tip modified spur gear pairs. It is observed that the tip relief modification has an excellent effect on the gear dynamic response. However, this effect is restricted until a certain amount of tip relief modification. After the optimum amount of tip relief modification, the dynamic loads are increased considerably. Thus, a computer program is developed to find the optimum amount of tip relief modification in MATLAB® for the gear designers. The program outputs are given for two different case studies. As a result of the study, the dynamic factor behaves like a “V form” according to the tip relief modification, and the dynamic force decreased approximately 25% for optimum profile modification. Dişli dinamiği; titreşim seviyeleri, yük taşıma kapasitesi ve gürültü üzerindeki dikkat çekici etkileri sebebi ile dişli çark tasarımındaki en kritik unsurlardan bir tanesidir. Dişli çark uç modifikasyonu endüstride dişli çarklar üzerindeki dinamik kuvvetleri azaltmak için kullanılan bir yöntem olarak bilinmektedir. Bu çalışmanın amacı; dişli uç modifikasyonunun düz dişli çarkların dinamik performansı üzerindeki etkilerinin anlaşılmasıdır. Bu kapsamda, düz dişli çarkların kavrama sürecine ve kavrama rijitliğinin hesaplamasına yönelik bir yöntem tanımlanmıştır. Dişli çark çiftinin dinamik cevabının bulunması için iki serbestlik dereceli bir dinamik model geliştirilmiştir. Dişli uç modifikasyonun dişli çarkların dinamik performansı üzerindeki etkilerinin incelenmesi için nümerik simülasyonlar hem standart hem de uç modifikasyonu uygulanmış dişli çark çiftleri için gerçekleştirilmiştir. Uç modifikasyonu uygulamasının dişli çarkların dinamik cevabı üzerinde mükemmel bir etkisi olduğu tespit edilmiştir. Ancak, belirtilen bu pozitif etkinin de belirli bir optimum değer ile sınırlı olduğu görülmüştür. Optimum dişli uç modifikasyonu miktarı aşıldıktan sonra dişli çark üzerindeki dinamik yükler ciddi bir şekilde artmaktadır. Bu çalışmada, MATLAB® ortamında dişli çark tasarımcılarının optimum uç modifikasyonu miktarını hesaplamasına olanak sağlayacak bir bilgisayar programı geliştirilmiştir. Program çıktıları iki farklı vaka çalışması için değerlendirilerek sunulmuştur. Sonuç olarak, dinamik faktörün profil modifikasyonu ile birlikte V formda değiştiği ve optimum modifikasyon değerinde yaklaşık olarak %25 azaldığı tespit edilmiştir.

In the current study, vibration analysis of functionally graded (FG) nano-sized beams resting on a elastic foundation is presented via a finite element method. The elastic foundation is simulated by using one-parameter Winkler type elastic foundation model. Euler-Bernoulli beam theory and Eringen's nonlocal elasticity theory are utilized to model the functionally graded nano-sized beams with various boundary conditions such as simply supported at both ends (S-S), clamped-clamped (C-C) and clamped-simply supported (C-S). Material properties of functionally graded nanobeam vary across the thickness direction according to the power-law distribution. The vibration behaviors of functionally graded nanobeam composed of alumina (Al2O3) and steel are shown using nonlocal finite element formulation. The importance of this paper is the utilize of shape functions and the Eringen's nonlocal elasticity theory to set up the stiffness matrices and mass matrices of the functionally graded nano-sized beam resting on Winkler elastic foundation for free vibration analysis. Bending stiffness, foundation stiffness and mass matrices are obtained to realize the solution of vibration problem of the FG nanobeam. The influences of power-law exponent (k), dimensionless nonlocal parameters (e(0)a/L), dimensionless Winkler foundation parameters (KW), mode numbers and boundary conditions on frequencies are investigated via several numerical examples and shown by a number of tables and figures.

In this paper, a three dimensional Computational Fluid Dynamics Model (CFD) model was generated for spray cooling of straight parts by using a single point nozzle. The numerical simulations of spray quenching were performed to investigate the cooling rate of a 22MnB5 hot steel blank commonly used material in the automotive industry. Experiments are carried out to examine infrared thermograph of hot steel blank surfaces during spray cooling process by using infrared thermal camera. Time dependent situations of surface temperatures, surface heat fluxes and cooling areas are investigated numerically. The 3D model with some assumptions is presented to improve the solution of numeric simulation and to meet the most appropriate acceptable results for spray cooling process. The developed 3D model will be used to investigate the heat transfer analysis of hot stamped parts during hybrid quenching to optimize the process parameters. The comparison of the numerical and experimental results showed that the presented approach can be effectively used to evaluate heat transfer during spray quenching with a single nozzle. With this research, it was clearly seen that the estimated cooling rates and the temperatures were in good agreement with the experimental cooling temperature data. By using the numerical results and experimental data obtained in this study, multi-nozzle spray apparatus which will be used to obtain different cooling rates on the parts by changing spray parameters such as spray height, spray angle, mass flow rate, the distance between nozzles and part etc. was developed for hybrid quenching process.

The drape behaviour of fabric is regarded as an aesthetic property, especially in the apparel and home textile industries. It has an influence on how well the appearance of a fabric in the end use. Fabric drape testing instrument developed by Cusick has been commonly used for the objective measurement of fabric drape behaviour. The device and the classic cut-and-weigh procedure is still the standard method of measuring drape. This method needs consumables and skilled operator for drawing, cutting, and weighing operations. To eliminate the disadvantages of this conventional system, image processing algorithm based on the Circular Hough Transform is developed to calculate the drape coefficient of fabrics in this study. Various woven and knitted fabrics were tested by both the conventional and the developed image processing methods. Drape results obtained from both systems represented a very strong relationship with a correlation coefficient of 0.99. As a result, fast, accurate and robust objective fabric drape test method has been developed.

This study investigates a long-term assessment of the wave energy resource propagated along the Algerian basin, based on a 39-year wave hindcast. The wave energy hindcast dataset was developed using the Simulating WAve Nearshore (SWAN) model, calibrated and validated [1] against wave measurements performed on the Algerian coast. A detailed spatial and local analysis was performed following the hindcast results. We have determined several parameters including; hourly, monthly, seasonal and annual variations of wave energy resources, the probability of occurrence distribution for different wave power ranges with different directions, the probability of calm sea states, the wave energy development index (WEDI) and the total annual wave energy and their distribution as a function of significant wave height and energy period. All these results enabled a very important benchmark for decision making regarding the future implementation and design of wave energy converters (WECs) and other offshore structures in the Algerian basin. Our findings have shown that the Algerian coasts are characterized by a considerable wave energy potential with a large hotspot area in the eastern coasts. Thus, we have recorded a significant variability in the wave energy characteristics available in each zone along the Algerian coast. The western zone was characterized by an average energy of ∼7.5 kW/m with a low monthly and seasonal variation (

WOS:000543104900020 This paper investigates the factors affecting the optimum insulation thickness and its pay-back period, such as heating and cooling energy requirements of building, lifetime, present worth factor, costs of insulation material and installation, costs of energy sources for heating and cooling, heating and cooling system efficiencies, and solar radiation. For this purpose, by considering two cities characterizing the hot and cold climatic conditions, the optimum insulation thickness and its payback period have been calculated and a detailed parametric analysis has been carried out. To achieve practical results, the ranges of the parameters considered in the study include the values typically reported in the literature. The variations in the optimum insulation thickness and the pay-back period with all parameters are presented in graphical form. Finally, order of importance and contribution ratios of the examined parameters on the optimum insulation thickness are determined with the help of Taguchi method. It is found that heating degree-days is the most efficient parameter on the optimum insulation thickness with an impact ratio of 27.33% of the total effect while the least efficient parameter is the efficiency of heating system with an impact ratio of 3.21%.

Purpose To compare the accuracy and repeatability of emerging machine learning based (i.e. deep) automatic segmentation algorithms with those of well-established semi-automatic (interactive) methods for determining liver volume in living liver transplant donors at computerized tomography (CT) imaging. Methods A total of 12 (6 semi-, 6 full-automatic) methods are evaluated. The semi-automatic segmentation algorithms are based on both traditional iterative models including watershed, fast marching, region growing, active contours and modern techniques including robust statistical segmenter and super-pixels. These methods entail some sort of interaction mechanism such as placing initialization seeds on images or determining a parameter range. The automatic methods are based on deep learning and they include three framework templates (DeepMedic, NiftyNet and U-Net) the first two of which are applied with default parameter sets and the last two involve adapted novel model designs. For 20 living donors (6 training and 12 test datasets), a group of imaging scientists and radiologists created ground truths by performing manual segmentations on contrast material-enhanced CT images. Each segmentation is evaluated using five metrics (i.e. volume overlap and relative volume errors, average/RMS/maximum symmetrical surface distances). The results are mapped to a scoring system and a final grade is calculated by taking their average. Accuracy and repeatability were evaluated using slice by slice comparisons and volumetric analysis. Diversity and complementarity are observed through heatmaps. Majority voting and Simultaneous Truth and Performance Level Estimation (STAPLE) algorithms are utilized to obtain the fusion of the individual results. Results The top four methods are determined to be automatic deep models having 79.63, 79.46 and 77.15 and 74.50 scores. Intra-user score is determined as 95.14. Overall, deep automatic segmentation outperformed interactive techniques on all metrics. The mean volume of liver of ground truth is found to be 1409.93 mL ± 271.28 mL, while it is calculated as 1342.21 mL ± 231.24 mL using automatic and 1201.26 mL ± 258.13 mL using interactive methods, showing higher accuracy and less variation on behalf of automatic methods. The qualitative analysis of segmentation results showed significant diversity and complementarity enabling the idea of using ensembles to obtain superior results. The fusion of automatic methods reached 83.87 with majority voting and 86.20 using STAPLE that are only slightly less than fusion of all methods that achieved 86.70 (majority voting) and 88.74 (STAPLE). Conclusion Use of the new deep learning based automatic segmentation algorithms substantially increases the accuracy and repeatability for segmentation and volumetric measurements of liver. Fusion of automatic methods based on ensemble approaches exhibits best results almost without any additional time cost due to potential parallel execution of multiple models.

In the literature, energetic and exergetic performance of Organic Rankine Cycle (ORC) were investigated by various researchers. The working parameters affecting the cycle's performance were determined but the impact weights and the order of importance of these parameters were not discussed with a statistical approach. In this context, nine fundamental process parameters such as working fluid type, pinch point temperature differences in the evaporator and condenser, superheating temperature, evaporation and condensation temperatures, heat exchanger effectiveness, turbine and pump efficiencies have been selected for the statistical evaluation. A comprehensive statistical analysis has been carried out to observe the effect of the parameters on the first and second law efficiencies of the ORC. The impact ratios and order of importance of these parameters on the system's performance indicators have been determined. While Taguchi method is performed to determine the optimum levels of each parameter, ANOVA method is used to obtain the impact weights of the parameters on objective functions. In addition to these methods, Grey Relational Analysis (GRA) method is used to optimize the multi-objective function. Evaporator temperature, turbine efficiency, effectiveness of heat exchanger, condenser temperature are obtained as main process parameters on the multiple performance characteristics of ORC and the impact ratios of these parameters are calculated as 31.37%, 19.53%, 16.64%, and 16.61%, respectively. The best condition for the multiple performance characteristics is determined as A(1)B(1)C(3)D(3)E(3)F(3)G(1)H(3)I(3) and under these operating conditions, the first and second law efficiencies of the system are found as 18.1% and 65.52%, respectively.

In this paper, an evaluation of the static and dynamic behavior of bimetallic spur gears with different gear parameters is performed numerically. Bimetallic lightweight spur gears working without a decrease in the performance of the gear mechanisms have many potential benefits in automotive and aerospace applications. A bimetallic spur gear consists of two metals which are steel on the gear teeth and aluminum on the hub region. The dynamic performance of these gears is evaluated by using a two degree of freedom (2-DOF) dynamic model. The finite element method is used to calculate maximum root stress for varying ring thicknesses and other gear parameters for gears with symmetric and asymmetric teeth. These stress values and the weight reduction ratios are taken into consideration to optimize the ring thickness. Tooth deflection is also calculated to determine tooth stiffness by finite element analysis (FEA). Dynamic simulations are carried out to investigate the effects of gear parameters on the dynamic force and static transmission error (STE). Sample simulation results are illustrated with numerical examples. The results indicate that, if properly designed, bimetallic gears can provide a high potential to reduce the weight in power transmission systems without adverse effects on stress and dynamic behavior. (C) 2019 Elsevier Ltd. All rights reserved.

There are various factors having an impact on the energetic and exergetic performance (i.e., COP and eCOP) of an absorption refrigeration systems (ARS) such as the temperatures of the generator, condenser, evaporator and absorber, effectiveness of solution, refrigerant and solution-refrigerant heat exchangers and isentropic efficiency of the solution pump. Many studies have focused on these process parameters, but the importance order and contribution ratios of the parameters due to thermodynamic performance have not been determined by using statistical methods. Firstly, in this study, cycles’ thermodynamic model is established and the variation of the COP and eCOP are calculated for different working conditions with different parameters ranges. The effects of these parameters on the COP and eCOP are examined separately on a statistical basis. The importance order of the parameters are determined by using Taguchi and ANOVA methods and the results are compared. Optimum operating conditions are determined by means of statistical analysis for the COP and eCOP. Under these operating conditions, the COP and eCOP of the system are calculated as 0.697 and 0.2829, respectively. Furthermore, for the simultaneous maximization of these two performance indicators, Taguchi-Grey Relational Analysis (GRA) is used. By using this analysis, importance order of the examined parameters on multiple performance characteristics are determined. The absorber and evaporator temperatures are the most efficient parameters on multiple performance characteristics with a contribution ratio of 29.66% and 26.34% of the total effect while the least efficient parameters are the pump efficiency and effectiveness of solution-refrigerant heat exchanger with a contribution ratio of 0.48% and 2.41%, respectively. For the best condition considering the multiple performance characteristics, COP and eCOP of the system are found as 0.6255 and 0.2829, respectively.

This study summarizes the greenhouse gas (GHG) emission levels and Sustainable Energy Action Plan (SEAP) of Bursa, where is an industrial, touristic, and historic metropolitan city with a dense population in Turkey. This study summarized direct (scope 1), indirect (scope 2), and other indirect (scope 3) GHG emissions. Urban GHG emissions including scope 1, 2, and 3 activities were determined as 14,148,597 tCO2e for 2016. Industrial fuel consumption, transportation, and residential heating activities were the main sources. GHG emission control sectors were determined according to the last consecutive workshops in 2017. Control actions, such as Energy efficiency/renewable energy applications in residential and commercial buildings, increasing the share of public transport in transportation, and reducing the number of private vehicles in traffic, were planned. Future projections for 2030 were estimated with and without reduction activities. Sectors (industry, agriculture, and animal husbandry) which are not within the jurisdiction of local governments or which cannot be intervened by local governments were excluded. It showed that with the mitigation measures to be implemented. Public transport problems, renewable energy conversion, and reduction of the green texture of the city are the main obstacles.

In the present study, the fatigue behaviour of a clutch diaphragm spring is investigated experimentally and numerically. Differential evolution optimisation algorithm and response surface methodology are used to define optimal variables of the diaphragm springs under constraints both minimum stress and required clamp load. The required clamp load is checked by the chi-square theorem vs. to target clamp load curve. Ten design variables are considered for creating a design of experiment with two steps, including finger shape optimisation with eight variables, load, and stress optimisation with two variables as the aim of maximum fatigue definition. One hundred seventy-five different designs are analysed numerically. As a result of the optimisation study, the optimum design is provided an endless lifetime subject to the required load, minimum stress, and minimum weight. The optimum design is manufactured and tested experimentally. Valeo

Performance characteristics of a novel cyclone with tangential inlet were presented in axial and reverse flow operation modes. 3-D and unsteady governing equations were used for the numerical solution of the two-phase turbulent flow in the cyclone separator. The Eulerian approach was used to solve the flow field, and the Reynolds Stress Model (RSM) with the scalable wall function was employed for the numerical study. The Lagrangian approach with the Discrete Phase Model was used to calculate the discrete phase by releasing particles from the inlet surface. CFD calculations were run for different geometric configurations to analyze the performance of the cyclones regarding pressure drop, cut-off diameter, and fractional efficiency. Axial and tangential velocity profiles are presented at the defined sections. The computational results of pressure drop, velocity field, and separation efficiency were also compared for the axial and reverse flow cyclones at the same flow rate. The results show that pressure drop and collection efficiency in reverse flow mode are higher than that of the axial flow operation. However, axial flow cyclones seem to be more efficient for small particles comparing to reverse flow cyclones.

This paper aims to examine the temporal variation of wave energy flux in the hotspot areas of the Black Sea. For this purpose, a 31-year long-term wave dataset produced by using a three-layered nested modelling system was used. Temporal variations of wave energy were determined at hourly, monthly, seasonal, and yearly basis at seventeen stations. Based on the results obtained, it can be concluded that the stations have very low fluctuations in mean wave power during the day. Mean wave power in the summer months shows a low difference between the stations, but in the winter months, there is a higher difference in wave power between the stations. This difference is more at the stations in the southwestern part of the Black Sea and much lower in the eastern Black Sea stations around Sinop, being in the middle of the southern coast of the Black Sea. In addition, it is concluded that mean wave energy flux presents a decreasing trend at all stations, but maximum wave power offers an increasing trend at most of the stations. Romanian Executive Agency for Higher Education, Research, Development and Innovation Funding (PN-III-P4-IDPCE-2016-0017)

In this paper, nine recent meta-heuristics have been employed to search for optimal design of an automatic planetary gear train. The function of the designed system is to automatically transmit power and motion in automobiles. Nine mixed decision parameters are considered in the optimisation procedure. The geometric conditions such as the undercutting, the maximum overall diameter of the transmission, as well as the spacing of multiple planets are taken into account to ensure an optimum design. All the above algorithms are tested both quantitatively and qualitatively for solution quality, robustness, and their time complexity is determined. Results obtained illustrate that the utilised approaches can effectively solve the planetary gearbox problem. Besides this, the comparative study indicates that roulette wheel selection-elitist differential evolution (ReDE) outperforms the other algorithms in terms of the statistical results, and FA has the best convergence behaviour. Meanwhile, multi-verse optimisation (MVO) and butterfly optimisation algorithm (BOA) performed better than the other used algorithms when computation time was considered. King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia

Photo Response Non-Uniformity (PRNU) is a camera imaging sensor imperfection which has earned a great interest for source device attribution of digital videos. A majority of recent researches about PRNU-based source device attribution for digital videos do not take into consideration the effects of video compression on the PRNU noise in video frames, but rather consider video frames as isolated images of equal importance. As a result, these methods perform poorly on re-compressed or low bit-rate videos. This paper proposes a novel method for PRNU fingerprint estimation from video frames taking into account the effects of video compression on the PRNU noise in these frames. With this method, we aim to determine whether two videos from unknown sources originate from the same device or not. Experimental results on a large set of videos show that the method we propose is more effective than existing frame-based methods that use either only I frames or all (I-B-P) frames, especially on YouTube videos., Comment: Revised (and accepted) version of the original submission. Minor changes have been brought to the original manuscript

WOS:000461154100006 Organic Rankine Cycle (ORC) is a system that uses working fluids with hydrocarbon components instead of water and generates power from the heat recovery of different heat sources. In this study, the exergy analysis of a simple ORC, which produces electrical energy with the help a geothermal source (125 degrees C), was performed. R123, R152a, R245fa and R600a were determined as the fluids to be used in the Cycle. In this analysis, which was carried out according to the pinch point temperature differences (5-20 degrees C) in the evaporator, the exergy performance of the cycle components was evaluated for the geothermal resource unit flow rate and the variation of the exergy efficiency of the system was calculated. With the increase of the pinch point temperature difference in the evaporator, the decrease of the system's exergy efficiency became maximal (11.7%) with the use of R152a as a refrigerant and the loss in the system's exergy efficiency became minimal (9.03%) with the use of R123 as a refrigerant.

For 20 years, antibacterial functionalization has been one of the most attractive research fields in the textile industry. Nowadays, globalization has spread the microorganisms everywhere and produced many epidemics and pandemics such as smallpox, cholera, tuberculosis, yellow fever, Spanish flu, and coronavirus. The textile materials treated with triclosan would be a strong alternative to obtain antibacterial function against microorganisms for the medical applications, such as face masks, lab coats, and wound dresses. This study aimed to investigate the characterization, antibacterial properties, and durability of triclosan on polyester, polyester/cotton, and cotton surfaces. The pure triclosan and presence of triclosan in solutions were detected by gas chromatography–mass spectrometry chromatograms. It can be seen that surfaces were homogeneously covered by triclosan on scanning electron microscope micrographs, and there were new bands on Fourier transform infrared spectra after treatments. Large inhibition zones around all surfaces were observed, and antibacterial activity slightly increased depending on increasing chemical concentrations. The samples demonstrated strong biocidal activity to bacteria for 3 h. They lost their antibacterial properties after washing, but they showed good antibacterial (bactericidal) properties and satisfactory durability to washes. The results show that triclosan is a highly effective and durable chemical on polyester and cotton surfaces for medical textile applications.

This paper introduces a new adaptive mixed differential evolution (NAMDE) algorithm for mechanical design optimisation problems. The algorithm uses a self-adaptive mechanism to update the values of mutation and crossover factors. Moreover, elitism is used where the best-found individual in each generation is retained. The performance of NAMDE is evaluated by solving 11 well-known constrained mechanical design problems and two industrial applications. Further, comparison results between NAMDE and other recently published methods, for the first problems, clearly illustrate that the proposed approach is an important alternative to solve current real-world optimisation problems. Besides this, new optimal solutions for some engineering problems are obtained and reported in this paper. For the coupling with a bolted rim problem, the objective function improved by 10%. Whereas for the spur minimisation problem, the final design provides a reduction in gearing mass by 7.5% compared to those published in previous works.

This work proposes a multi-surrogate-assisted optimisation and performance investigation of several newly developed metaheuristics (MHs) for the optimisation of vehicle crashworthiness. The optimisation problem for car crashworthiness is posed to find the shape and size of a crash box while the objective function is to maximise the total energy absorption subject to a mass constraint. Two main numerical experiments are conducted. Firstly, the performance of different surrogate models along with the proposed multi-surrogate model is investigated. Secondly, several MHs are applied to tackle the proposed crashworthiness optimisation problem by employing the best obtained surrogate model. The results reveal that the proposed multi-surrogate model is the best performer. Among the several MHs used in this study, sine cosine algorithm is the best algorithm for the proposed multi-surrogate model. Based on this study, the application of the proposed multi-surrogate model is better than using one particular traditional surrogate model, especially for constrained optimisation. Thailand Research Fund (TRF)

We present techniques for steganalysis of images that have been potentially subjected to steganographic algorithms, both within the passive warden and active warden frameworks. Our hypothesis is that steganographic schemes leave statistical evidence that can be exploited for detection with the aid of image quality features and multivariate regression analysis. To this effect image quality metrics have been identified based on the analysis of variance (ANOVA) technique as feature sets to distinguish between cover-images and stego-images. The classifier between cover and stego-images is built using multivariate regression on the selected quality metrics and is trained based on an estimate of the original image. Simulation results with the chosen feature set and well-known watermarking and steganographic techniques indicate that our approach is able with reasonable accuracy to distinguish between cover and stego images.